The syscall link_create not protected by bpf_disable_instrumentation, accessing percpu data bpf_prog_active should use cpu local_lock when kprobe_multi program attach. Fixes: 0dcac2725406 ("bpf: Add multi kprobe link") Signed-off-by: Tao Chen --- kernel/trace/bpf_trace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 3ae52978cae..f6762552e8e 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2728,23 +2728,23 @@ kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, struct pt_regs *regs; int err; + migrate_disable(); if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) { bpf_prog_inc_misses_counter(link->link.prog); err = 1; goto out; } - migrate_disable(); rcu_read_lock(); regs = ftrace_partial_regs(fregs, bpf_kprobe_multi_pt_regs_ptr()); old_run_ctx = bpf_set_run_ctx(&run_ctx.session_ctx.run_ctx); err = bpf_prog_run(link->link.prog, regs); bpf_reset_run_ctx(old_run_ctx); rcu_read_unlock(); - migrate_enable(); out: __this_cpu_dec(bpf_prog_active); + migrate_enable(); return err; } -- 2.48.1